There are a wide variety of different types of agricultural machines. Such machines include combine harvesters (or combines). A combine harvester extracts grain from a field and moves it through a variety of different devices in the combine. For instance, the grain can be moved to a separator and then to a cleaning shoe. After the grain is cleaned at the cleaning shoe, it is often then moved to a clean grain tank.
The cleaning shoe has a number of different controllable subsystems which can be set to operate differently, under different harvesting conditions. Some of the controllable subsystems can include the fan speed of a cleaning shoe fan, as well as the size of openings in the sieve and chaffer portions of the cleaning shoe. Often, combine harvesters have a variety of different sensors that sense variables, such as grain loss, etc. These sensor signals are monitored to control different controllable subsystems in the cleaning shoe based upon the sensed variable.
However, the performance of the cleaning shoe also varies based upon the rate at which grain is fed into the cleaning shoe. The feed rate of the grain provided to the cleaning shoe may vary widely, based upon slight changes in machine speed, whether the machine is traveling uphill or downhill, differences in the crop yield at different locations in the field, among a wide variety of other things.
The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.